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f L1 HOM~_Sb t1KE QRANTH OFFICE Mr. Thomas Malecek, District Ranger Rio Grande National Forest Divide Ranger District 13308 West Highway 160 Del Norte, Colorado 81132 9 August 2004 Alan D. Cox Project Manager -Bulldog R~ry~~ y~i; , Re: Bulldog Mine Reclamation Project, Mineral County, CO Water Quality Monitoring in Windy Gulch . Deaz Mr. Malecek: . ~ ZQD~ On,/slOoo ~nE2% ~~4~ %gy» This letter provides an update on the water quality monitoring activities that have been conducted by Homestake in Windy Gulch as per our letter to you of July 14, 2004. The monitoring that has been conducted in Windy Gulch follows the plan described in our letter to the Forest Service dated August 23, 2002. As per this monitoring plan, the goal for reclamation efforts is to meet Agricultural Standazds in Windy Gulch at the tower weir, which is near the confluence of Windy Gulch and Willow Creek. Although the reclamation activities in the Windy Gulch azea were substantially completed in the fall of 2002, Windy Gulch did not flow below Bachelor Road during 2003 due to the regionally dry conditions. As a result, no monitoring data could be collected in 2003. Windy Gulch began to flow below Bachelor Road in late March 2004 and monitoring activities were implemented according to the plan. Monitoring activities have included the measurement of flow at the upper weir (at Bachelor Road) and the lower weir (at the mouth of Windy Gulch). Monthly water quality samples were also collected at each location for laboratory analysis. See attached map for locations of the two sampling points. Flows measured during 2004 by data loggers located at the upper and lower weirs in Windy Gulch aze shown on Figure 2. Flows varied from about 0.25 to 0.5 cfs in late Mazch to a peak of about 2 to 3 cfs in eazly May. Flow at the lower weir ceased in eazly June whereas flow at the upper weir continued at less than 0.1 cfs into mid-June. This behavior is typical of other years when flow has been monitored in Windy Gulch prior to the most recent work in Windy Gulch associated with construction of the cutoff walls and streamflow bypass structures in the the 9700 and 9360 waste rock disposal azeas. Water quality samples were taken at the upper and lower weir locations on Mazch 26, April 20 and May 16, 2004. No sample was taken in June because the lower weir was dry. The results of the chemical analyses are shown in Table I. For some constituents, both total and dissolved analyses aze shown. The total analyses generally show higher constituent levels since they include any sediment contained in the water as well as the dissolved constituents. A comparison of the results to the Agricultural Standazds set as water quality goals in the August 23, 2002 plan is included. Average concentrations from 16 samples taken during the 1998 to 2001 period (i.e., prior to the final reclamation activities in Windy Gulch) aze also shown for comparison.